Currently the pallet-uniques allow the following action for privileged accounts of a collection:

• The owner of an nft-class can destroy ALL items of this class
• The admin of an nft-class can burn ANY item of this class (Not if locked since Disallow burning externally locked nfts #13054)
• The admin of an nft-class can transfer ANY item of this class (Not if locked since Disallow burning externally locked nfts #13054, or frozen collection/item)
• The owner of an nft-class can set the MAX SUPPLY of this class
• The freezer of an nft-class can freeze ANY item of this class
• The freezer of an nft-class can freeze the WHOLE class

IMO for downstream users of this pallet as an implementor of the traits nonfungibles::* this has some negative impact about the assumption one will likely make:

• Owning an NFT means it can not arbitrarily be removed from your ownership

Maybe Solutions

• Destroying a collection is only possible if all items are owned by the owner again
• Lock or Hold as part of nonfungibles::Mutate & destroying a collection is not allowed if any item is still locked/on hold